GREENSBORO, NC -- Scientists estimate about 71% of the earth is covered by it.

It has three different states: liquid, solid and gas. You can't live without it. Yes, we are talking about water.

"I'm Tyreek and my question is, 'why is water sometimes clear and why it is sometimes blue?' "

If you cup water in your hand it does look clear and colorless. But when you look at a body of water, like the ocean, it looks blue or greenish. And what is done to filter your drinking water? We went to the City of Greensboro Water Resources department for the answer.

"This plant the Townsend Water Plant, treat water from the lake and this is water we get hear from the lake is oil water. To get the particles together we add coagulant this make the particles come together the particles coming together you can see that water and how bad it is."

After that the city settles the particles in the water after they settle they become more clear . The next step is filtration. the particles you can see the particles become really fine and then next is filtration and that will take the fine particle out too so we have clear water. Water is blue due to the wave lengths, blue wave lengthens in the spectrum the prism. Your reds, greens, browns and orange absorbed light a lot quicker than blue, blue has that a lot longer wave length so it penetrates deeper into the water, so the deeper the water is the bluer it is

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